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Is Clear Air Turbulence becoming more common?

flightradar24.com

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Re: Is Clear Air Turbulence becoming more common?

#71

Post by _moof »

w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

An increase in the frequency of clear air turbulence doesn't necessarily entail an increase in reportable accidents and incidents. The NTSB is only notified when a specific set of criteria are met. See 49 CFR Part 830 for details. If the increase in turbulence is all light to moderate turbulence with no serious injuries, there's nothing to report to the NTSB.

Re: Is Clear Air Turbulence becoming more common?

#72

Post by oceanplexian »

throwup238 wrote: post #64
dclowd9901 wrote: post #50

Earlier quoted context omitted.

Right, and those two years are generationally distant. Another question I have is if pilots have a stable mechanism (that is, an unchanged objective sensor or something) that records the CAT or if it’s recorded by pilots, whose sensitivity to CAT might differ over time. Didn’t mention in the article how it’s measured.

CATs are recorded in pilot reports using terms like "light", "moderate", "severe", and "extreme" which each have a definition. I.e. severe is "Occupants are forced violently against seat belts or shoulder straps. Unsecured objects are tossed about. Food service and walking are impossible." I think only severe and extreme turbulence need mandatory reports and the lower two levels are a bit more subjective ("Food servi…

Unsecured objects being tossed around has no real meaning, it’s about controllability of the aircraft.

I’m a pilot and it’s been a while since I went over PIREPS but generally severe is rarely used, severe means the turbulence is so bad you can no longer control the aircraft. What most passengers imagine as severe is probably light turbulence. Most of the time it’s not even reported. As a side note if you’re ever on an aircraft and not secured at all times, you’re making a huge mistake.

Re: Is Clear Air Turbulence becoming more common?

#73

Post by oceanplexian »

antoniojtorres wrote: post #66
aidenn0 wrote: post #54

Earlier quoted context omitted.

"Fewer than forty feet of altitude change" A 40 foot drop is pretty scary; by comparison, an NCAA dive platform is 33 feet.

I agree. It’s funny to think of the gap between safety and scary when talking about turbulence. Large planes can take an absolute beating and be completely fine, but it could feel like the end of the world inside.

A modern airliner is rated to something like 3-4G's including the safety factor, probably much more if it's not at max takeoff weight. I'm sure you could do a Mythbusters-style test but I'd assume most passengers would pass out from the negative and positive G forces long before the aircraft structurally failed.

Re: Is Clear Air Turbulence becoming more common?

#74

Post by alfalfasprout »

_moof wrote: post #71
w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

An increase in the frequency of clear air turbulence doesn't necessarily entail an increase in reportable accidents and incidents. The NTSB is only notified when a specific set of criteria are met. See 49 CFR Part 830 for details. If the increase in turbulence is all light to moderate turbulence with no serious injuries, there's nothing to report to the NTSB.

This deserves to be the top comment. Turbulence accident statistics are only going to ever reflect clear air turbulence if the aircraft sustained detectable damage or passenger(s) sustain serious enough injuries.

Re: Is Clear Air Turbulence becoming more common?

#75

Post by stouset »

rootusrootus wrote: post #58
stouset wrote: post #48

Earlier quoted context omitted.

When was the last time a commercial airliner crashed due to turbulence?

Best I can tell, 1966. https://en.m.wikipedia.org/wiki/BOAC_Flight_911

Then I think we can safely worry about other things than turbulence :)

Re: Is Clear Air Turbulence becoming more common?

#76

Post by vlovich123 »

MadnessASAP wrote: post #57
vlovich123 wrote: post #51

Earlier quoted context omitted.

Do we really not record turbulence sensor data off the airplanes and download it when they’re on the ground? I’m also surprised that these airplanes have on demand satellite TV streaming to these airplanes but airlines claim that it costs 100k to add that to existing planes. There’s just no way it’s 100k per plane - there must be a cheap way to retrofit the data without having it be reliable since it’s opportunistic.…

> Do we really not record turbulence sensor data off the airplanes and download it when they’re on the ground? No, accelerometer data is only recorded to the FDR. Which has a limited storage window (1-24 hours depending on the aircraft) and is slow to download requiring moderately specialized equipment and a technician to carry out the task. Aircraft downtime and technician hours are both expensive and in short suppl…

I find it hard to believe that the headsets they are using for software and hardware meet that level of criteria. They’re clearly using off-the-shelf parts. Some amount of care is called for sure, but 100k to apply a software patch or tweak the tech in FDRs which are swappable and upgradable? A flight recorder is 10k. You can’t tell me it costs 90k to install a new one capable of sending data over the satellite link in bursts. Clearly other countries and airlines with a similar safety record and cost of living and salaries are able to accomplish the feat.

Re: Is Clear Air Turbulence becoming more common?

#79

Post by withinboredom »

oceanplexian wrote: post #72
throwup238 wrote: post #64

Earlier quoted context omitted.

CATs are recorded in pilot reports using terms like "light", "moderate", "severe", and "extreme" which each have a definition. I.e. severe is "Occupants are forced violently against seat belts or shoulder straps. Unsecured objects are tossed about. Food service and walking are impossible." I think only severe and extreme turbulence need mandatory reports and the lower two levels are a bit more subjective ("Food servi…

Unsecured objects being tossed around has no real meaning, it’s about controllability of the aircraft. I’m a pilot and it’s been a while since I went over PIREPS but generally severe is rarely used, severe means the turbulence is so bad you can no longer control the aircraft. What most passengers imagine as severe is probably light turbulence. Most of the time it’s not even reported. As a side note if you’re ever on…

I watched Cast Away. I always wear my seat belt.

Re: Is Clear Air Turbulence becoming more common?

#80

Post by rdtsc »

w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

Could be an inverse relationship, too - the more frequently they occur the more experience, training and guidance the pilot, and the other crew members get to manage it: how to control the the airplane, urge passengers to wear seatbelts more, etc.
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